diff --git a/pbl_common/audit.py b/pbl_common/audit.py
index cac9913..e834aeb 100644
--- a/pbl_common/audit.py
+++ b/pbl_common/audit.py
@@ -87,12 +87,13 @@ def build_audit_record(action, table=None, row_id=None, detail=None, ctx=None,
                        tenant_id=None, actor_id=None, actor_type=None,
                        trace_id=None, result='ok', created_at=None):
     """构造一条审计记录 dict（tenant_id 打头，不落库）。"""
-    tid = normalize_tenant(tenant_id if tenant_id is not None else _safe_tenant(ctx))
-    if not tid:
+    raw_tid = tenant_id if tenant_id is not None else _safe_tenant(ctx)
+    if raw_tid is None or str(raw_tid).strip() == '':
         raise ParamInvalidError(
             code=PBL_E_TENANT_MISSING,
             message='审计写入缺少 tenant_id（审计同样强制租户打头）',
             detail={'action': action, 'table': table})
+    tid = normalize_tenant(raw_tid)
     if ctx is None:
         try:
             ctx_obj = current_context(strict=False)